Samsung 2433 BW vertical purple line

Greetings all,

I've assembled a system 3 weeks ago (AMD 955 BE, Sapphire Radeon HD4890 Vapor-X, Gigabyte Ma-790-xt ud4p, Corsair DDR3 2x2 GB etc.) which is showing its power on the brand new Samsung 2433BW 24" LCD screen.

3 days ago while surfing the web, a purple vertical line appeared on the screen and persisted there altough I've changed several resolutions, restarted the PC and turned off/on the monitor.

The next day the purple vertical line disappeared and now the monitor seems to be working normally.

I've read that one possible cause of this might be the low quality of the LCD panel - however in that case the line would remain, while mine disappeared.

I've informed the computer shop where I've bought the monitor, they advised in case the purple line is continuously on screen, they will take it for checking and eventually replace my monitor with a new one.

Anyone else had a similar problem?

Also, the documentation says "Samsung 2433BW", but on the monitor it's only written "Samsung 2433".

One last thing, though it's not for this forum - can you recommend me an application to fully test my GPU and see if it's overheating or not?

Thanks in advance.